One-pot Synthesis Of Pyrrolo Research Articles

A one-pot microwave green synthesis of pyrrolo[1,2-c]imidazole-1-one analogs and structural studies

An efficient green method developed as a one-pot synthesis of pyrrolo[1,2-c]imidazole-1-one derivatives under microwave conditions via two-component using a substoichiometric quantity of water. The conformational and structural studies were conducted through DFT optimization and single-crystal X-ray diffraction. The molecular packing was mediated through hydrogen bonding and C-H...π interactions. The Hirshfeld surface analysis highlighted significant H-H interactions in all compounds, with compound 2a exhibiting the highest percentage. HOMO and LUMO studies revealed compound 2a as more stable and less reactive. The molecular electrostatic potential provided the charged proportionality along with the molecular surface. The drug-likeness properties suggested that compounds 2b, 2c, 2d, 2e, 2f, 2g, and 2i possess favorable properties for potential pharmaceutical applications.

Chlorophyll-catalyzed tandem oxidation /[3+2] cycloaddition reactions toward the construction of pyrrolo[2,1-a]isoquinolines under visible light

Chlorophyll as a green, cheap, and affordable natural pigment was used in the one-pot synthesis of pyrrolo[2,1-a]isoquinoline scaffold under visible light. This photocatalytic approach has handled oxidation/[3 + 2] cycloaddition/aromatization cascade reaction using air as the final oxidant. Under this condition, a vast variety of N-substituted tetrahydroisoquinolines were treated with dipolarophiles in good to excellent yields.

An efficient and facile access to highly functionalized pyrrole derivatives.

A straightforward and one-pot synthesis of pyrrolo[3,4-c]pyrrole-1,3-diones via Ag(I)-catalyzed 1,3-dipolar cycloaddition of azomethine ylides with N-alkyl maleimide, followed by readily complete oxidation with DDQ, has been successfully developed. Further transformation with alkylamine/sodium alkoxide alcohol solution conveniently afforded novel polysubstituted pyrroles in good to excellent yields. This methodology for highly functionalized pyrroles performed well over a broad scope of substrates. It is conceivable that this efficient construction method for privileged pyrrole scaffolds could deliver more active compounds for medicinal chemistry research.

One-pot synthesis of pyrrolo[1,2-a]quinoxaline and pyrrolo[1,2-a]pyrazine derivatives via the three-component reaction of 1,2-diamines, ethyl pyruvate and α-bromo ketones

A simple synthetic protocol has been developed involving the three-component reaction between 1,2-diamines, ethyl pyruvate and α-bromo ketones in the presence of FeCl3 as a catalyst. A number of pyrrolo[1,2-a]quinoxaline and pyrrolo[1,2-a]pyrazine derivatives were synthesized in excellent yields using this protocol.

One-pot synthesis of pyrrolo[1,2-a]pyrazines via three component reaction of ethylenediamine, acetylenic esters and nitrostyrene derivatives

Abstract An effective route to pyrrolo[1,2- a ]pyrazines is described via reaction of ethylenediamine, acetylenic esters and nitrostyrene derivatives in the presence of 20 mol% of sulfamic acid.

One-Pot Synthesis of Pyrrolo[1,2-a]quinolin-1-ones by the Cyclocondensation of 5-Hydroxy-1-arylpyrrolidin-2-ones with Dicarbonyls

A one-pot synthesis of pyrrolo[1,2-a]quinolin-1-ones has been developed from the reactions of 5-hydroxy-1-arylpyrrolidin-2-ones with 1,3-dicarbonyl compounds under the promotion of H3PO4/P2O5 or HOAc/H2SO4. The pyrrolo[1,2-a]quinolin-1-ones are formed by two-step reactions, that is, the coupling of N-acyliminium ion intermediates produced from 5-hydroxy-1-arylpyrrolidin-2-ones with 1,3-dicarbonyls and subsequent Friedel–Crafts reactions of the resulting ketone with the aryl ring.

One-Pot Synthesis of Pyrrolo[1,2-a]quinoxaline Derivatives via Iron-Promoted Aryl Nitro Reduction and Aerobic Oxidation of Alcohols

Here, we describe a new one-pot method to synthesize 4,7-substituted pyrrolo[1,2-a]quinoxalines and related heterocyles through a cascade of redox reactions/imine formation/intramolecular cyclization. This procedure tolerates readily available substituted 1-(2-nitrophenyl)pyrrole derivatives and aliphatic or benzylic alcohols as starting materials using iron powder and acidic conditions. This is the first example of constructing N-heterocycles via iron-mediated aryl nitro reduction and aerobic oxidation of alcohols in one pot.

One-Pot Synthesis of Pyrrolo[3,2-f]- and Pyrrolo[2,3-h]quinoline Derivatives: Observation of an Unexpected Mechanistic Pathway

SYNLETT 2012, 23, 717–722xx.xx.2012 Advanced online publication: 24.02.2012 DOI: 10.1055/s-0031-1290565; Art ID: B65611ST © Georg Thieme Verlag Stuttgart · New York Abstract: One-pot synthesis of pyrrolo[3,2-f]and pyrrolo[2,3h]quinolines were obtained starting from substituted 5-aminoindoles, benzaldehydes, and phenylacetylenes in the presence of La(OTf)3 as a catalyst in good yields. The indole moiety in 5-aminoindole is believed to be mainly responsible for the observation of unexpected mechanistic pathway to the formation of pyrrolo[2,3h]quinoline.

One-Pot Synthesis of Pyrrolo[3,2-d]pyridazines and Pyrrole-2,3-diones via Zirconocene-Mediated Four-Component Coupling of Si-Tethered Diyne, Nitriles, and Azide

A one-pot synthesis of pyrrolo[3,2-d]pyridazine derivatives via zirconocene-mediated four-component coupling of one Si-tethered diyne, two nitriles, and one azide is reported. When TMSN(3) was used, pyrrole-2,3-diones were formed in good yields. Further condensation of these highly functionalized pyrrole-2,3-diones with hydrazine and hydroxylamine afforded useful pyrrole-fused heterocycles.

ChemInform Abstract: An Efficient One-Pot Synthesis of Pyrrolo(4,3,2-ij)isoquinoline Derivatives by a Consecutive Aza-Wittig/Electrocyclic Ring Closure/ Intramolecular Acylation Process.

Iminophosphorane, ethyl 5-ethoxycarbonyl-2-methoxy-α-[(triphenylphosphoranylidene)amino]cinnamate (4) reacts with aliphatic and aromatic isocyanates in toluene at 170 o C to give directly the corresponding pyrrolo[4,3,2-if]isoquinolines 8 in moderate yields

One-Pot Synthesis of Pyrrolo[2,1-a]isoquinoline-1-carboxamide Derivatives via a Four-Component Reaction

An effective route to functionalized 1,2,3,10b-tetrahydropyrrolo[2,1-a]isoquinoline-1-carboxamide derivatives is described. This involves reaction of N-alkyl-3-oxobutanamides, which result from the addition of amines to diketene, and dibenzoyl­acetylene in the presence of isoquinoline. The reactive 1:1 intermediate obtained from the addition of isoquinoline to diben­zoyl­-acetylene is trapped by OH acids such as N-alkyl-3-oxobutan­amides to produce the pyrrolo[2,1-a]isoquinoline-1-carboxamide derivatives.